Introduction of Taper Drill Rod
It also used in the mining of natural stone mines. The biggest competitor in the extension drill rod market is taper drills rods. The competition is fierce and the product performance is reliable, but each has its own characteristics. The taper drill rods also has a hexagonal clamping surface that can provide torque for the hexagonal sleeve of the rock drill. Usually there is also an upset collar to allow the rock drill to accurately impact the top of the taper drill. The other end of the drill bit is equipped with a taper drill bit.
Generally, the hole diameter is mainly 32mm or 34mm for quarrying, and the hole depth is above 0.6 meters, which will increase with the increase of the air leg feed length. Due to the fact that it is faster than the overall drilling length, the drilling is straighter, the meter path is longer, and the drilling cost per meter is lower, taper drilling tools are increasingly taking the overall drilling market, especially in the mining and quarrying industries.
Different rock formations and rock drill conditions require different tapers. When used with high frequency and high impact power hydraulic rock drills in medium rock and grindstone hard rock conditions, large tapers of 11 degrees and 12 degrees are usually used. 11° and 12° tapers are commonly used in modern bench drills. However, when used in conjunction with low frequency and low impact power rock drills in softer rock conditions, a small taper of 7° is usually used. When using 11° and 12° drilling tools, there is a problem that the drill bit cannot be stuck. 7° drilling tools can also be used.
In addition, when using hand-held, air-legged pneumatic rock drills and hydraulic bench drills to work in soft rock, the 4.8° (ie 4°46') drill tool can also be used to prevent the bit from getting stuck or falling off. In addition, a single drill rod is used for shallow holes (≤2.0m), and a drill rod is used for deeper holes (>2.0m) to prevent excessive bending stress. There are three grades of taper drills provided, ranging from collar size to drill tip length from 600mm to 11,200mm
